Trump should have never agreed to written responses.
I knew this would be the next step.
Stop cooperation with Mueller.
Appeasement will not work.
Trump must shut down the corrupt investigation.
I believe his acting director of DOJ will end it. And convey appropriate message to Mueller what the consequences are, without actually stating it.
In old fashioned Hoover FBI form. Call him to meeting. Tell him what he should do. Then lay the actual folder right in front of his eyes.
End of game.